Preliminary Study on Callus Differentiation of Hermaphrodite Papaya

With calluses of hermaphrodite papaya as the tested material and MS as the basic medium, the effects of different plant growth regulators and their combinations on adventitious bud induction of calluses and rooting induction of sterile buds were investigated. The results showed that 6-BA and TDZ all showed certain induction effect on callus differentiation of papaya; the induction effect of 6-BA was better than that of TDZ, and the optimum concentration of 6-BA was 0.05 mg/L. GA3 could promote the induction effect of 6-BA for on callus differentiation. The optimum medium combination for inducing the callus differentiation of papaya was MS ＋ 6- BA 0.5 mg/L ＋ GA3 1.0 mg/L. Compared to NAA, IBA was more suitable for inducing the rooting of adventitious buds. The optimum rooting-induction medium combination was MS ＋ IBA 0.3 mg/L.

Effects of 2,5-Norbornadiene （NBD） on Physiological and Biochemical Responses of Fresh-cut Winter Squash

Ethylene is one of the most important plant hormones that regulate physiological responses, maturity and senescence of postharvest fruits and vegetables. The determination of its role in the wound-healing response of fruits and vegetables is helpful in understanding the wound responses. 2,5-Norbornadiene （NBD）, inhibitor ethylene binding were used to determine the effect of ethylene action on wound-induced response of fresh-cut winter squash, a kind of vegetables known to produce ethylene markedly after cutting. The effect of NBD on the physiological and biochemical changes of fresh-cut winter squash was investigated in this experiment. The results showed that NBD had great effects on physio-biochemical metabolism of fresh-cut winter squash. Ethylene production was inhibited significantly by NBD. NBD also had an inhibition effect on polyphenol oxidase （PPO）, peroxidase （POD） and phenylalanine ammonia lyase （PAL） activity. The effect of NBD on lipoxygenase （LOX） activity and superoxide dismutase （SOD） was not obvious. NBD treated sample showed a more rapid increase in catalase （CAT） activity, which may help in healing the damage of the tissue. These information are important in understanding the fundamental biology of wound response and in the development of new technology to hasten wound-healing and, thereby, to minimize costly wound-related problems in fresh-cut industry.

Measurement of soluble solids content in watermelon by Vis/NIR diffuse transmittance technique

Watermelon is a popular fruit in the world with soluble solids content （SSC） being one of the major characteristics used for assessing its quality. This study was aimed at obtaining a method for nondestructive SSC detection of watermelons by means of visible/near infrared （Vis/NIR） diffuse transmittance technique. Vis/NIR transmittance spectra of intact watermelons were acquired using a low-cost commercially available spectrometer operating over the range 350-1000 nm. Spectra data were analyzed by two multivariate calibration techniques： partial least squares （PLS） and principal component regression （PCR） methods. Two experiments were designed for two varieties of watermelons [Qilin （QL）, Zaochunhongyu （ZC）], which have different skin thickness range and shape dimensions. The influences of different data preprocessing and spectra treatments were also investigated. Performance of different models was assessed in terms of root mean square errors of calibration （RMSEC）, root mean square errors of prediction （RMSEP） and correlation coefficient （r） between the predicted and measured parameter values. Results showed that spectra data preprocessing influenced the performance of the calibration models. The first derivative spectra showed the best results with high correlation coefficient of determination [r=0.918 （QL）; r=0.954 （ZC）], low RMSEP [0.65 °Brix （QL）; 0.58 °Brix （ZC）], low RMSEC [0.48 °Brix （QL）; 0.34°Brix （ZC）] and small difference between the＇RMSEP and the RMSEC by PLS method. The nondestructive Vis/NIR measurements provided good estimates of SSC index of watermelon, and the predicted values were highly correlated with destructively measured values for SSC. The models based on smoothing spectra （Savitzky-Golay filter smoothing method） did not enhance the performance of calibration models obviously. The results indicated the feasibility of Vis/NIR diffuse transmittance spectral analysis for predicting watermelon SSC in a nondestructive way.

Effect of Different Treatment on Anther Callus Formation and Browning in Balsam Pear （Mornordica charantia L.）

Brown callus derived from anther limited the application of anther culture in balsam pear. In order to establish a more perfect regeneration system from anther cultuer, the effects of low temperature pretreatment, 2,4-dichlorophenoxyacetic acid （2,4-D）, vitamin C （Vc） and silver nitrate （AgNO3） on callus induction and browning in anther culture of balsam pear （Momordiea charantia L.） were investigated. The results showed that after pretreatment at 4 ℃ for 1 day, callus induction rate was the highest and browning rate was the lowest. Anthers on MS medium supplemented with 2,4-D 0.5 mg/L formed more and better callus. The medium supplemented with Vc or AgNO3 was advantageous to the induction of callus and reduction of browning. When cultured on medium supplemented with 50 mg/L Vc or 5 mg/L AgNO3, callus induction rate was the highest and browning rate was rather low.

老瓜头和我

老瓜头有一手种瓜的好本事,他种的瓜又大又甜,十里八村都知道。老瓜头脾气倔也是出了名的,每当香瓜开园,他请大家吃瓜,分文不取,但如果有人偷瓜伤了他的瓜秧,他会拎着烟袋去你家刨门。我和老瓜头之间还有一段有趣的＂瓜缘＂。那年我9岁,上小学三年级。一天放学路上,遇到经常在一起玩耍的小伙伴狗剩儿和胖墩儿,他俩神秘兮兮地带我来到村头一棵大榆树下，从树洞里掏出两个瓜塞给我。

Gualou Xiebai Banxia Decoction(瓜蒌薤白半夏汤) Inhibits NF-kappa B-dependent Inflammation in Myocardial Ischemia-reperfusion Injury in Rats

Objective: To evaluate the myocardial protective effect of Gualou Xiebai Banxia decoction (瓜蒌薤白半夏汤GXBD) and explore the mechanisms of inhibition of NF-kappa B activation and blockade of inflammatory responses induced by ischemia-reperfusion in rats. Methods: Twenty-four Sprague Dawley (SD) rats were randomly divided into three groups. Rats in the treatment group received GXBD (13 g crude drug/kg) for three weeks, while rats in the model control and normal control groups received equal volumes of distilled water. On the 22nd day, rats in the ischemia-reperfusion (I/R) control and GXBD-treated groups underwent 30 min occlusion of the left anterior descending (LAD) coronary artery, followed by 120 min reperfusion. Electrocardiogram was recorded, and the activities of cardiac enzymes, cytokines, and NF-кB were assessed after I/R. Results: Compared with the I/R control group, GXBD treatment restored the activity of the specific myocardial-injury marker creatine kinase (CK) and lactate dehydrogenase (LDH), and inhibited the inflammatory response involving the nuclear factor-кB (NF-кB) pathway, including down-regulation of interleukin (IL)-1β and IL-6, and up-regulation of IL-10 gene expression. Conclusion: GXBD strongly reduced myocardial impairment in our I/R model, including inhibition of NF-кB activation and inflammatory cytokine responses.

Responses of phospholipase D and lipoxygenase to mechanical wounding in postharvest cucumber fruits

This study was to investigate the responses of phospholipase D（PLD） and lipoxygenase（LOX） to mechanical wounding in postharvest cucumber（Cucumis sativus L.cv.Biyu-2） fruits.Membrane-associated Ca2＋ content,activities and gene expression of PLD and LOX,and contents of phosphatidylcholine（PC）,phosphatidylinositol（PI）,and phosphatidic acid（PA） were determined in cucumber fruits following mechanical wounding.Results show that PLD and LOX activities increased with the PLD and LOX mRNAs which are upregulated upon wounding,while membrane-associated Ca^2＋ content decreased.Accompanying with the increase of PLD and LOX activities,accumulation of PA and losses of PC and PI were observed in all fruits,but there were differences of degrees between wounded and control fruits.Results suggest that PLD and LOX might be the main hydrolytic enzymes of phospholipids in postharvest cucumber fruits participating in the mechanical wounding injury.The activation of PLD and LOX might be the result of gene expression,which could be This study was to investigate the responses of phospholipase D（PLD） and lipoxygenase（LOX） to mechanical wounding in postharvest cucumber（Cucumis sativus L.cv.Biyu-2） fruits.Membrane-associated Ca^2＋ content,activities and gene expression of PLD and LOX,and contents of phosphatidylcholine（PC）,phosphatidylinositol（PI）,and phosphatidic acid（PA） were determined in cucumber fruits following mechanical wounding.Results show that PLD and LOX activities increased with the PLD and LOX mRNAs which are upregulated upon wounding,while membrane-associated Ca2＋ content decreased.Accompanying with the increase of PLD and LOX activities,accumulation of PA and losses of PC and PI were observed in all fruits,but there were differences of degrees between wounded and control fruits.Results suggest that PLD and LOX might be the main hydrolytic enzymes of phospholipids in postharvest cucumber fruits participating in the mechanical wounding injury.The activation of PLD and LOX might be the result of gene expression,which could be stimulated by the Ca^2＋ flowing from the membrane to the cytoplasm upon receiving the wounding signals.